Temperature is one of the most basic physical quantities in the nature and temperature measurement is of great importance for cognition of natures of materials in the nature. Rapid temperature measuring method using ferromagnetic particles is a brand new temperature measuring method calculating temperature by detecting magnetization varies of ferromagnetic particles and by certain model relationship, and featuring non-invasion, ultrahigh speed (on nanosecond level) and high accuracy. The temperature measuring method using ferromagnetic particles may be widely used in fields such as laser heating, rapid metal solidification and temperature measurement of motors for its non-invasion and high speed.
Development of engineering technology brings in many heat conduction problems such as ultrashort duration of heat effect, ultrahigh density of transient heat flux and ultrafast temperature variation. Conventional Fourier's Law is no longer applicable for those extraordinary heat conductions of ultrahigh speed, and heat conduction effect not following the Fourier's Law occurring under the extraordinary heat conductions is known as the non-Fourier heat conduction effect. Unfortunately, it is difficult for techniques and devices in prior art to accurately detect temperature variation in such short durations. The problem of ultrashort action duration may be overcome by rapid and noninvasive temperature measurement by ferromagnetic particles and the temperature variation process is monitored for further research.Particular temperature measuring problems such as pulsating flame temperature measurement in an engine combustion chamber of an aircraft and temperature measurement of high-temperature thermal processing furnace, and welding and casting by high-frequency heating often occur in the field of aerospace, which cannot be resolved effectively by conventional temperature measuring method. Accordingly, temperature measuring devices should feature fast response and high accuracy which can be realized by combining noninvasive rapid temperature measurement by ferromagnetic particles and temperature conduction. Therefore, Noninvasive rapid measuring technology with high accuracy is still an urgent problem to be resolved.